קחי מטלית אחרת; המטלית הזאת כבר רטובה מדי.

Because קחי is the imperative form used when speaking to one female.

• קח = take! to one male
• קחי = take! to one female
• קחו = take! to more than one person

So this sentence is being said to a woman or girl.

Hebrew uses את only before a definite direct object.

Here, מטלית אחרת means another cloth, which is indefinite, so there is no את.

Compare:

• קחי מטלית אחרת = take another cloth
• קחי את המטלית = take the cloth

So the absence of את tells you the object is not specific/definite.

Because in Hebrew, adjectives usually come after the noun.

So:

• מטלית אחרת = another cloth
  • מטלית = cloth
  • אחרת = other / another

This is the normal Hebrew order:

• noun + adjective

Also, אחרת matches מטלית because מטלית is feminine singular.

Because the adjective must agree with the noun in gender and number.

מטלית is a feminine singular noun, so the adjective also has to be feminine singular:

• masculine singular: אחר
• feminine singular: אחרת
• masculine plural: אחרים
• feminine plural: אחרות

So:

• דבר אחר = another thing
• מטלית אחרת = another cloth

Because in Hebrew, when you say this/that + noun, the noun is usually definite, so it takes ה־.

That means the normal pattern is:

• ה + noun + this/that word

So:

• המטלית הזאת = this cloth
• הספר הזה = this book
• הילדה הזאת = this girl

In other words, Hebrew does not usually say the equivalent of cloth this without marking the noun as definite.

That is the normal Hebrew position for demonstratives like this and that when they modify a noun.

So Hebrew says:

• המטלית הזאת = literally the cloth this
• הספר הזה = literally the book this

This is different from English, where this comes before the noun.

Also notice agreement:

• masculine singular: הזה
• feminine singular: הזאת
• masculine plural: האלה
• feminine plural: האלה

Since מטלית is feminine singular, it takes הזאת.

For the same reason as אחרת: the adjective must agree with מטלית.

Since מטלית is feminine singular, the adjective must also be feminine singular:

• רטוב = wet, masculine singular
• רטובה = wet, feminine singular

So:

• המגבת רטובה = the towel is wet
• הבד רטוב = the fabric is wet

מדי means too or excessively.

So:

• רטובה מדי = too wet

In Hebrew, מדי usually comes after the adjective:

• יקר מדי = too expensive
• קשה מדי = too difficult
• רטובה מדי = too wet

This is different from English, where too comes before the adjective.

כבר usually means already.

Here it gives the sense of:

• this cloth is already too wet
• or this cloth is too wet by now

It often adds the idea that a condition has already been reached.

So:

• המטלית הזאת רטובה מדי = this cloth is too wet
• המטלית הזאת כבר רטובה מדי = this cloth is already too wet

The second version sounds a little more like the speaker is reacting to the current situation.

A simple pronunciation guide would be:

K'khi matlit akhéret; ha-matlit ha-zot kvar retuvá midáy.

A few notes:

• קחי begins with a throaty/rough kh sound, like German Bach or Scottish loch
• stress is roughly on:
  • akhéret
  • hazót
  • retuvá
  • midáy

If you do not yet produce the kh sound naturally, that is very common for English speakers.

Yes. The semicolon is just punctuation linking two closely related parts:

• קחי מטלית אחרת; המטלית הזאת כבר רטובה מדי.

You could also write:

• קחי מטלית אחרת. המטלית הזאת כבר רטובה מדי.

The meaning stays the same. In speech, it would simply sound like a pause between two related statements.

You mainly change the imperative קחי.

• to one woman: קחי מטלית אחרת
• to one man: קח מטלית אחרת
• to several people: קחו מטלית אחרת

The second clause stays the same:

• המטלית הזאת כבר רטובה מדי

So the full versions would be:

• קחי מטלית אחרת; המטלית הזאת כבר רטובה מדי.
• קח מטלית אחרת; המטלית הזאת כבר רטובה מדי.
• קחו מטלית אחרת; המטלית הזאת כבר רטובה מדי.